Lettering scriber



A ril 7, 1964 D. K. CROOK 3,127,679

LETTERING SCRIBER Filed Dec. 29, 1960 2 Sheets-Sheet l L\ in 28 38 32 INVENTOR D'AVID K. CROOK ATTORNEY April 7, 1964 D. K. CROOK 3,127,679

LETTERING SCRIBER Filed Dec. 29, 1960 FIG. 5 7o 2 Sheets-Sheet 2 INVENTOR DAV! D K. CROOK United States Patent Office 3,127,679 Patented Apr. 7, 1964 3,127,679 LETTERING SCRIBER David K. Crook, R0. Box 156, Olney, Md. Filed Dec. 29, 1960, Ser. No. 79,473 2 Claims. (Cl. 33-24) (Granted under Title 35, US. Code (1952), see. 266) A nonexclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to a novel lettering scriber. More particularly it relates to a scriber for inscribing letters or figures on a plate from a lettering guide.

Specifically, the invention relates to a scriber for engraving letters or figures on plastic-coated surfaces by means of a needle guided by a stencil remote from the engraving site.

In the art of map-making, it has become standard practice to engrave the various legends, names, and the like onto a sheet of flexible, transparent plastic material having a soft, removable, opaque coating and using the soengraved sheet as a photographic negative in the subsequent processing steps. The engraving is generally done by means of a stylus and a lettering guide.

Prior to the present invention, all engraving lettering devices were either of the horizontal pantograph type or those having a vertical-radial swing about a fulcrum. The pantograph type is cumbersome, while those instruments having a vertical radial action could not be used on soft surfaces such as films, plastics, and the like.

It is, therefore, one object of this invention to provide a lettering scriber which is small and convenient to use. Another object is to provide such a scriber which can be used to engrave letters and other figures on soft plastic surfaces and on such surfaces having a thin removable coating. A further object is to provide a lettering scriber by means of which it is possible to select any desired ratio of size between the engraved figure and the template figure without changing templates. Still another object is to provide a lettering scriber in which the scribing point bears with a uniform pressure on the work surface.

These and other objects which will be apparent to those skilled in the art are achieved by means of the instrument of this invention.

In accordance with the present invention, there is provided an instrument having a vertical fulcrum in which a. horizontal motion of a lettering guide is transmitted through the vertical fulcrum to a horizontal scribing or engraving point whereby the point moves in a horizontal plane and applies a uniform cutting pressure to the surface over the entire area to be engraved.

In general, the scriber of the present invention comprises a first horizontally movable member carrying a guide point for tracing a letter in a template, a second horizontal movable member carrying a scribing point, a vertically adpustable fulcrum, and connecting means through the fulcrum for transmitting the horizontal movements of the guide point to the scribing point to produce a corresponding horizontal motion in the latter. The position of the fulcrum is variable so that the ratio of movement of the guide point to the scribing point may be varied, thereby to make it possible to select the ratio of size of the letters or figures being engraved to the size of the template. In this manner, it is possible to engrave letters of varying selected sizes without changing the template. Further means are provided for maintaining a uniform pressure of the scribing point on the surface to be engraved and means for raising the scribing point from the surface.

The present invention is more fully described below, reference being made to the accompanying drawings in which FIGURE 1 is a perspective view of the complete assemy;

FIGURE 2 is a section on line 22 on FIGURE 1 showing the method of assembling the lower horizontally movable member which carries the scribing point;

FIGURE 3 is a plan section on line 33 of FIGURE 1 showing the fulcrum assembly;

FIGURE 4 is a section on line 44 of FIGURE 1 showing the assembly of the upper horizontally movable member which carries the guide point;

FIGURE 5 is a plan section on line 55 of FIGURE 1 showing the means for raising and lowering the scribing point; and

FIGURE 6 is an enlarged view showing the raising and lowering means in greater detail.

The instrument of this invention comprises a movable support column 1 having, at its upper end, a perpendicular platform 3 disposed in a gene-rally horizontal plane. Platform 3 may either be made integral with support column 1 or it may be rigidly secured thereto any suit able manner. Platform 3 is provided with a groove 4 in which is supported a removable template 5. The latter is secured to the platform by any suitable means such as clamp 6 and thumbscrew 7.

Also secured to column 1 is a bracket 8 having a rectangular hole 9 out completely through most of the area of its horizontal faces. A U-shaped member 10', having flat parallel faces 11 and 12, is slidably mounted on bracket 8 so that the horizontal face of the latter is included between the parallel faces 111 and 12. A further bracket 13 is rigidly secured by one end to, or made integral with, U-shaped member 16 and extends up and back in the direction of column 1 so that free end 14 is over template 5. End 14 is enlarged to constitute a cylinder large enough to accommodate small chuck member 15 which has a needle 16, serving as a guide point, inserted in its lower end and secured therein by set screw 17. The chuck is normally urged downward by spring 18 inside cylindrical end 14 so that the needle 16 is in pressure contact with template 5. The needle may be raised from the template by pulling upward on knob 19 and turning the latter so that tongue 20 is lifted out of slot 21 and rests on edge 22.

U-shaped member 10 carries a spherical socket 2-3 which extends through the opening 9 and is secured to the faces 11 and 112 by means of nut 24. An elongated cylindrical member 25, having a ball 26 at its end, operates in spherical socket 23 to complete a ball and socket joint.

Column 1 is provided at its lower end with a perpendicular extension 27 parallel to bracket 8. opening 28 is cut in the face of extension 27 to accommodate a second chuck member 29 which has a threaded hollow upper portion 30* and is slidably mounted on extension 27 by means of washers 31 and 3-2, and secured by means of nut 40. The lower portion of chuck 29 is drilled out to accommodate spindle 33 which carries scribing needle 34 secured by means of set screw 35. The spindle itself is secured in chuck 29 by means of set screw 36 extending through an elongated slot 37. A spring 38 behind th spindle normally urges the latter outward; but some longitudinal movement is permitted by slot 37.

Hollow upper end 36 of chuck 29' carries a ball 39 which serves as a bearing for spherical end 41. of rod 42. Rod 42 extends upward and is sufficiently long to extend into cylindrical rod 25. A spring 43 inside rod 25 applies a downward pressure on rod 42. It will be apparent that, with members 10' and 29 slidably mounted on parallel brackets 23 and 27, respectively, any movement of member 13, which is secured to member 10, will be through rod 42 to chuck 29, and therefore, to scribing needle -34.

-To control the aforesaid movements, rod 42 is mounted on fulcrum assembly indicated generally by 44. This assembly comprises a ball 45 mounted in spherical bearing 46 so as to be able to rotate in all directions, and is secured therein by means of a removable side member 47 bolted to the body of bearing 46 by bolts 48 and 4?. Bearing 46 is mounted on split base 50, and may be either integral therewith or rigidly secured thereto by any suitable means. Base 50' is provided with a groove 51 which fits over vertical rail 52 on column *1. Thus base 50, carrying bearing 46, is vertically slidable on rail 52 and may be secured in any desired position by tightening screw 53.

The ball fulcrum 45 is provided with a hole along a diameter through which rod 42 is passed. The hole is sufficiently large to permit an easy sliding motion of rod 42. This manner, any desired ratio of movements between guide point 16 and scribing point 34, and thus a ratio of size of engraved letter to size of template, may be obtained by varying the position of ball fulcrum 45, the ratio being determined by the proportion of the length of rod 42 which extends above and below ball 45.

To raise or lower the scribing point, column 1, upon which the above-described assembly is mounted, is provided with a slot 54 along its entire length. A vertically stationary column 55, either rigidly secured to or made integral with base 2, is provided along its length with a rail 56 which fits int-o slot 54. Thus column 1 is vertically movable on column 55. Column 1, and thus scribing point 34 is maintained in a normally raised position by means of spring 57 which is compressed between the under side of platform 3 and the knob 58 of adjustment screw 59. Pressure of the spring is adjusted by turning adjustment screw 59 in the necessary direction. Once a desired pressure has been obtained, it may be so maintained by fixing screw 59 in its position with set screw 65. To lower the scribing point into contact with the surface to engraved, downward pressure is applied on lever 61 which is pivoted to column 1;' on pivot 62 to rotate in a vertical plane. End 63 of lever 61 extends into slot 64 in column 55. Thus, when downward pressure is applied on lever 61, end 63 applies an upward pressure against the top of slot 64, forcing column 1 downward on column 55 against the pressure of spring 57. The lever is kept depressed as long as lettering is in progress. As soon as the lever is released, spring 57 raises the point 34 from the work surface.

It is not necessary to shift the entire instrument after engraving each letter on the work surface. Base 2 is provided with feet 65 and 66 set sulficiently far apart to permit several letters to be engraved in the space between them. Column 55 is mounted on a horizontally movable bas 67 which slides on rail 68 secured to base 2. A pinion 69, carried on a shaft (not shown) rotated by knob 70, meshes with the teeth of rack 71. T he pinion assembly is mounted on horizontally movable base 67, and rotating knob 70 causes the entire assembly comprising the template, guide point, fulcrum, and scribing point to travel from side to side.

To use the instrument, it is placed on the surface to be engraved (not shown), with scribing point 34 over the place where the work is to begin and lever 61 is depressed to bring the scribing point into contact with the work surface. Guide point 16 is then dropped into a letter or number on template and used to trace the letter or number. The horizontal movement of point 16 is transmitted by means of member to chuck assembly l9 through rod 42 and ball 45. The chuck assembly moves horizontally on bracket 27, causing scribing point 34 to trace the same pattern or letter as guide point 16. While lever 61 is used to raise or lower the scribing assembly, the pressure of point 34 on the coated surface is largely governed by the raising force of compressed spring 57 which is adjustable, as previously described, by means of 58 on screw 59.

As was also described above, it will be apparent from the geometry of the assembly that the ratio of size of the scribed letter to the size of the template letter will be governed by the vertical posit-ion of ball fulcrum 45 and the relative proportions of rod 42 which extend to either side of the fulcrum.

I claim:

1. A scribing instrument comprising a base; a first support member mounted for horizontal movement on said base; a second support member vertically disposed and mounted for vertical movement on said first support member; templat holding means secured to the second support member near the top of said second support member adapted to hold a template in a horizontal plane; a guide member movably mounted on the second support member near the top of said second support member adapted to move in a horizontal plane and follow a pattern on a template; scribing point support means movably mounted on the second support member mounted near the bottom of said second support member and adapted to move in a horizontal plane; a scribing point adapted to contact a surface to be engraved secured to sair scribing point support means; a vertically adjustably spherical fulcrum mounted on said second support member between said guide member and said scribing point support means; rigid means resiliently connected to both said guide member and said scribing point support means and slidably connected through said spherical fulcrum whereby a horizontal motion of the guide member produces a corresponding horizontal motion in the scribing point; means for raising and lowering said second support member on said first support member; and means for horizontally moving said first support member on said base.

2. In a device of the character described having a base,- a first support member horizontally movable on said base, a second support member vertically movable on said first support member, and means mounted on the second support member near the top of said second support member for holding a template in a horizontal position, upper planar support means rigidly secured to the second sup port member in a horizontal plane near the top of said second support member having an upper and a lower surface and provided with an opening in said surfaces through the entire thickness, first slidable support means adapted to slide over said upper planar support means in a plane parallel to its openings, guide means rigidly secured to said first slidable support means and adapted to contact a template held in said template holding means, a first spherical socket rigidly secured to said first slidable support means extending through the opening in said upper planar support means adapted to move inside said opening when said first slidable support means is moved about the surface of said upper plan ar support means, lower planar support means rigidly secured to the second support member in a horizontal plane near the bottom of said second support member having an upper and a lower surface and provided with an opening in said surfaces through the entire thickness, second slidable support means adapted to slide over said lower planar support means parallel to the planes of its surfaces, a member rigidly secured to said second slidable support means extending through the opening in said lower planar support means having a scribing point resiliently mounted at its lower end and provided with an upwardly extending spherical socket at its upper end, a vertically adjustable spherical fulcrum mounted on the second support member between said upper and lower planar support means, and elongated rigid means slidably extending through a diametral opening in said spherical fulcrum, one end of said elongated means being rotatably mounted in the spherical socket secured in the second slidable support means and the other end of said elongated means being resiliently connected to said first slidable support means.

(References on following page) 5 6 References Cited in the file of this patent FOREIGN PATENTS UNITED STATES PATENTS 1234-,867- Germany May 23, 1911 190,797 Ware May 15, 1 77 184,511 Great Britain Aug. 18, 1922 767,938 Gray Au 1 1904 5 284,471 Great Britain Feb. 2, 1928 1,180,906 Clark Apr. 25, 1916 $0 9,442 Belgium Mar. 15, 1952 2,746,152 Deakin May 22, 1956 

1. A SCRIBING INSTRUMENT COMPRISING A BASE; A FIRST SUPPORT MEMBER MOUNTED FOR HORIZONTAL MOVEMENT ON SAID BASE; A SECOND SUPPORT MEMBER VERTICALLY DISPOSED AND MOUNTED FOR VERTICAL MOVEMENT ON SAID FIRST SUPPORT MEMBER; TEMPLATE HOLDING MEANS SECURED TO THE SECOND SUPPORT MEMBER NEAR THE TOP OF SAID SECOND SUPPORT MEMBER ADAPTED TO HOLD A TEMPLATE IN A HORIZONTAL PLANE; A GUIDE MEMBER MOVABLY MOUNTED ON THE SECOND SUPPORT MEMBER NEAR THE TOP OF SAID SECOND SUPPORT MEMBER ADAPTED TO MOVE IN A HORIZONTAL PLANE AND FOLLOW A PATTERN ON A TEMPLATE; SCRIBING POINT SUPPORT MEANS MOVABLY MOUNTED ON THE SECOND SUPPORT MEMBER MOUNTED NEAR THE BOTTOM OF SAID SECOND SUPPORT MEMBER AND ADAPTED TO MOVE IN A HORIZONTAL PLANE; A SCRIBING POINT ADAPTED TO CONTACT A SURFACE TO BE ENGRAVED SECURED TO SAIR SCRIBING POINT SUPPORT MEANS; A VERTICALLY ADJUSTABLY SPHERICAL FULCRUM MOUNTED ON SAID SECOND SUPPORT MEMBER BETWEEN SAID GUIDE MEMBER AND SAID SCRIBING POINT SUPPORT MEANS; RIGID MEANS RESILIENTLY CONNECTED TO BOTH SAID GUIDE MEMBER AND SAID SCRIBING POINT SUPPORT MEANS AND SLIDABLY CONNECTED THROUGH SAID SPHERICAL FULCRUM WHEREBY A HORIZONTAL MOTION OF THE GUIDE MEMBER PRODUCES A CORRESPONDING HORIZONTAL MOTION IN THE SCRIBING POINT; MEANS FOR RAISING AND LOWERING SAID SECOND SUPPORT MEMBER ON SAID FIRST SUPPORT MEMBER; AND MEANS FOR HORIZONTALLY MOVING SAID FIRST SUPPORT MEMBER ON SAID BASE. 